


Flirting With Your Best Friend for Dummies

by poppyfields



Category: Haikyuu!!
Genre: Best Friends, Fake/Pretend Relationship, Falling In Love, First Love, Flirting, M/M, Oblivious, POV Matsukawa Issei, Pranks and Practical Jokes
Language: English
Status: Completed
Published: 2021-01-26
Updated: 2021-01-26
Packaged: 2021-03-12 12:07:15
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,868
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29010258
Author URL: https://archiveofourown.org/users/poppyfields/pseuds/poppyfields
Summary: Oikawa and Iwaizumi are in love with each other. It's obvious. To their best friends at least. For some reason, though, neither of them know how to communicate it, so Mattsun and Makki decide to take it upon themselves to show them how to flirt. To show them how to turn their friendship into something more.(Alternate title: taking the joke a little too far)
Relationships: Hanamaki Takahiro/Matsukawa Issei, Iwaizumi Hajime/Oikawa Tooru
Comments: 8
Kudos: 123





	Flirting With Your Best Friend for Dummies

It was obvious Oikawa liked Iwaizumi. So obvious that Mattsun and Makki had exchanged a look the very first day they met the two friends, a look that Mattsun immediately recognized, even though he’d only met Makki earlier that day. It was a look they would end up sharing often.

If Mattsun had to guess, he’d say there was probably only one person who knew Oikawa and didn’t know about his crush. Iwaizumi. It wasn’t quite as immediately obvious, but Mattsun and Makki had seen enough over the years to know Iwa liked him back. Still, the two childhood friends were consistently oblivious to the other’s feelings.

By the time they started third year Matsukawa could tell Makki was starting to get tired of it.

“Oh my god Oikawa,” Makki groaned one day, drawing their friend’s eye from where it was watching Iwaizumi’s receding back, “That’s not how you flirt.”

“What?” Oikawa’s eyes went wide in a mix of fake shock and real panic, “Flirting? I- I wasn’t flirting.”

He’d been teasing Iwaizumi for his hair, which was, to be fair, insanely messy today. It was clear to Mattsun he’d been trying to get his friends attention, but it had also been clear Iwaizumi had no idea.

“You have to do it like this,” Makki told him, ignoring Oikawa’s objections. 

Like what? Mattsun wondered for about one full second before suddenly Makki’s face was right in front of his, and his long fingers were weaving their way into his hair.

“Aww, Mattsun,” Makki’s voice was crooning and overly sweet, like he was talking to a child, or a puppy, “You’re hair’s so cute when it’s messy.”

“What the fuck, Makki,” Mattsun objected, swinging his arms up to push the hands out of his hair.

“I’m not doing that,” Oikawa insisted, face turning red, “And I wasn’t even flirting! I don’t even-”

“We know you like Iwaizumi, Oikawa,” Makki turned to him, away from Mattsun, as if this didn’t involve him at all.

“I- I don’t even- What are you-”

Mattsun watched as Oikawa and Makki started to argue, but he couldn’t think of anything to say. He could hardly follow what they were saying. What was Makki doing? Why could he still feel his fingers in his hair?

He never really got a chance to ask, to clarify, because by the time he was brought back into Oikawa and Makki’s conversation the topic had changed completely. He thought it was probably nothing, though. He thought he probably shouldn’t make a big deal about it.

* * *

“Iwa-chan, you never have lunch with us anymore,” Oikawa whined one day as the four of them moved through the hallway.

“This is literally the first time I’ve done something else in like two weeks,” Iwa argued, “And I don’t see why it even matters.”

Oikawa just pouted, “Fine, go have lunch with your traitor friends then you traitor.”

Iwaizumi rolled his eyes as he peeled off from the group, turning into a classroom. Makki shook his head and clucked his tongue, disapprovingly.

“Now, come on, have some balls Oikawa.”

“Oh god, not this again,” the captain groaned. It had been more than a month since the hair incident.

“You know what you wanted to say, just do it. Like this,” Makki turned to Mattsun, dramatically grasping both his hands in his own. This time Mattsun was a little more prepared, but it still took him by surprise, “Matsukawa, I want to see your gorgeous face every hour of every day,” this time his voice wasn’t high and sweet, but low and romantic, “Please don’t eat lunch with your other friends, I’ll get terribly, insufferably jealous.”

Ok. Mattsun was starting to get what they were doing. They were making fun of Iwaizumi and Oikawa, right? And Makki was the Oikawa, so that meant he was the Iwaizumi. Ok. He could do that.

“I want to be with you too, baby,” he made his voice a little raspy, in a failed attempt to imitate their friend, “But I’m afraid of my own feelings, so I have to distance myself from you.”

Makki laughed at this, and Oikawa was burning bright red. Ok. Mission accomplished.

“I hate you,” Oikawa bristled, turning away, likely because he could tell he was blushing, “That is not what I wanted to say, I don’t have feelings for Iwa-chan, and-” He turned back for a second, just to glare at Matsukawa, “And Iwa-chan _definitely_ doesn’t have feelings for me.”

Mattsun and Makki exchanged a look, their signature, _oh my god this guy’s so ridiculously in love_ look. Mattsun was glad he was actually on board with the joke this time. It made it a lot easier, a lot more fun.

“Oh, so if Iwaizumi _definitely_ doesn’t have feelings for you,” Makki pointed out, “Then does that mean you might possibly like him?”

“Fuck off, Makki, I’m telling you I don’t.”

“Ok loverboy,” Mattsun grinned, “Then you’ll be ok to get lunch without him today? You won’t sulk.”

Oikawa straightened his back, as if unsure if he had already been sulking.  
“I won’t.”

* * *

Now that Matsukawa was in on the joke, they started doing it a lot more frequently. When either he or Makki caught Oikawa or Iwaizumi doing anything even remotely flirty, they would replicate it, generally a lot more exaggerated, to each other. It made Oikawa blush every single time.

Oikawa was the usual target of the teasing, mostly because it was really fun to tease him, but one day Oikawa had to go home after practice, and the other three were going to get ramen.

“Are you going to miss me, Iwa-chan?” Oikawa taunted, making Mattsun and Makki both a little proud.

“I’m not,” Iwaizumi didn’t even take a second to consider, but he didn’t look Oikawa in the eyes, “Just go home already.”

Oikawa pouted, “You’re so mean.”

“I’m not going to fucking miss you Oikawa, I see you every day.”

Oikawa frowned, shot a little _I told you so_ look at Makki, and turned on his heel to leave. Mattsun was shaking his head before he even took two steps, looking disappointedly at Iwaizumi.

“Iwa, Iwa, Iwa,” he was still shaking his head. Iwaizumi frowned up at him, “You’re playing too hard to get. He’s going to think you actually don’t like him.”

Makki nodded, sagely, but Iwa looked confused.  
“What are you talking about?”

“You gotta be a little more playful, a little more captivating,” Mattsun raised his hand to settle on the back of Makki’s neck, slowly rustling the bottom of his hairline with his thumb. He moved his face close to Makki’s ear, and lowered his voice to a rumble, “Do you want me to miss you, Makki?”

Makki looked over at him, a wide, impressed smile on his face. “Now that was captivating,” he turned back to their friend, “Take notes, Iwa-chan.”

This time, Iwaizumi was even redder than Oikawa normally got, redder than Mattsun had seen him before.

“What the fuck are you guys doing? I don’t- I’m not gonna- I-” He struggled for a minute to find a single word to say, “What the fuck was that?”

“That,” Mattsun explained, dropping his hand off Makki’s neck, “Is what you should have done.”

“Yeah, if you ever want this whole,” Makki gestured around Iwaizumi as if he could see his aura or something, “ _Iwaizumi Hajime, Oikawa Tooru, platonic besties for life_ thing to go anywhere.”

“Go-” Iwaizumi looked like he choked on the word, face still bright red and eyes wide, “I don’t want it to _go_ anywhere. I- I’m not in love with Oikawa!”

“Woah!” Mattsun and Makki said simultaneously, exchanging a quick look before smiling back at Iwaizumi. “No one said anything about love,” Mattsun finished. 

“I think he might be in love with Oikawa,” Makki mused.

“You know what, Makki, I think you might be right,” Mattsun grinned, “I mean, I was just thinking he wanted to hit, but maybe-”

“I’m not!” Iwaizumi practically yelled, the red of his face suddenly reading as anger instead of embarrassment, “And I don’t want to fuck him either, you fucking weirdos.” Mattsun and Makki just snickered, “Whatever,” Iwa finished, “You two can get ramen yourselves.”

Their snickering continued as Iwa stormed off.  
“You think he’s mad, Mattsun?”  
“I think he might be, Makki.”

* * *

Now that they were teasing Iwaizumi, too, the boys found themselves in a sort of strange position. Both the victims knew they were being teased, but neither knew about the other, so they would make fun of Iwa when Oikawa’s back was turned and then make fun of him when Iwaizumi’s back was turned. 

Mattsun and Makki loved it, though, and it soon became like second nature. Whenever they could get away with it, they gave their little lessons on how to flirt, and though they were still met with blushes and groans and _shut the fuck up_ s, Oikawa had now admitted to them he did like Iwa, and Iwa had at least stopped trying to argue that he didn’t.

“Ok, but I don’t need flirting advice from you two bastards,” was Oikawa’s current objection to the teasing, “If anything I should be teaching you guys.”

“Ok, yeah sure, flirting with girls,” Makki admitted, because it would be stupid not to, because Oikawa had a million girls begging to be with him and he and Mattsun had never even had one, “but flirting with your male best friend that you’ve been in love with for years? That’s a different story.”

Oikawa rolled his eyes, “Yeah, and you’re the expert on that?”

“Of course I am,” Makki responded casually, wrapping an arm around Mattsun’s head and rubbing his earlobe between his fingers, “Aren’t I, baby?”

Mattsun felt a little knot in his throat. What was all that? Why was Makki’s hand on his ear? Who were they making fun of now? He knew better than to ruin one of Makki’s jokes with his questions, though, and he was sure it would all make sense if he just went along with it.

“Best I’ve ever seen,” Mattsun shrugged, enjoying the shocked look on Oikawa’s face, even if he was a little behind on the joke himself.

“Wait, you two aren’t actually-” Oikawa’s eyes were darting between the two of them, though Mattsun noted how little his eyes actually had to move to do that. Makki’s face was so close to his, their cheeks were almost touching.

“Wouldn’t you like to know,” Makki hummed, tilting his head the final little distance, so his forehead was resting on the side of Mattsun’s face. They were really close. Really really close. Mattsun didn’t know if he’d ever been this close to his friend before.

“You’re not,” Oikawa said, as if trying to convince himself more than anything else, “There’s no way.”

Mattsun was still unaware what the final result of this joke was meant to be, but Makki was still playing with his ear, so it must still be ongoing.  
“And what makes you so sure?”

“You’re-” Oikawa squinted at them, and Mattsun did his best to keep his expression blank, unreadable, “You’re not.”

Makki frowned, taking his hand off Mattsun’s ear and backing away just a little, enough to look at him and shrug.

“He’ll believe what he wants to believe I guess.”

“Don’t worry baby,” Mattsun smiled, playfully grabbing the end of Makki’s nose. Was that too much? It felt like too much. It was funny though. “We don’t have to prove ourselves to him.”

Makki laughed a little, the nose thing might have been too much.

“I knew it,” Oikawa insisted, “You’re not.”

“Aw, I just couldn’t help but laugh,” Makki argued, “My Mattsun’s so cute.”

Here Matsukawa laughed. _My Mattsun_? It just sounded so weird. And Makki could say it so well. Like he really was used to saying it. Like they really were together. Like they really were in love. Hanamaki was so funny.

* * *

It was new year's day, only months until their graduation, and the four of them had gathered at a restaurant in the evening. A restaurant that, while not entirely shady, they knew didn’t check IDs when serving alcohol, as long as they weren’t in school uniforms. A restaurant that they came to fairly regularly.

Iwaizumi and Oikawa sat across the table from Matsukawa and Hanamaki, and they’d all already shared one bottle of sake.

Iwaizumi was just starting to tell the story of his most recent job interview when Makki made eye contact with Oikawa so pointed that even Mattsun noticed, and Makki was beside him, barely in his field of vision.

Makki raised one hand just a bit, making sure he could see Oikawa’s eyes drop to it, before he sank it below the table and rested it on Mattsun’s thigh. Mattsun looked over at him, confused, but Makki was glaring across the table at Oikawa.

 _Do it,_ Makki mouthed, quite obviously.

Oikawa lowered his brow, glancing worriedly at Iwaizumi, who was too wrapped up in his story to notice anything, before looking back at Makki.

 _I’m not putting my fucking hand on his fucking thigh,_ Oikawa mouthed back, though the only words Mattsun could actually make out by reading lips were the curses. The rest he mostly filled in based on context.

Makki faked a cough, “Pussy!” before leaning a little closer to Mattsun and letting his hand dip a little further down his thigh. “Excuse me,” he smiled at Iwaizumi, “Go on.”

Mattsun was fairly certain, no entirely certain, Oikawa couldn’t see where his hand was under the table, so he didn’t really get why his hand was so fucking low between his thighs. The sake probably wasn’t helping, but he was starting to feel a little hot at the back of his neck. Maybe he should push Makki’s hand away.

“I think I’m gonna take a piss,” Iwaizumi announced, standing up from the table.

“Very classy, Hajime,” Makki teased, not moving his hand from Mattsun’s leg. Could Iwaizumi see it when he got up? He didn’t know they were teasing Oikawa, he might just think they were, like, dating or something.

Iwaizumi left without saying anything though, so either he didn’t notice or he didn’t think to comment, and before Mattsun could tell Makki to move his hand, both of Makki’s hands were slamming down on the table.

“Just touch his fucking leg Oikawa, it’s not that hard.”

“I’m not touching his fucking leg, Makki, that’s weird.”

“It’s not that weird,” he turned to Mattsun, replacing the hand on his leg, “It’s not that weird, right Mattsun?”

Maybe it was the alcohol, or the feeling of both of his friends looking at him so intensely, or, probably, the hand on his thigh, a little higher than it had been earlier, but Matsukawa started to feel his face get a little hotter.

“I don’t know, it’s kind of weird, Makki.”

Makki dropped his jaw into a face of betrayal, and he pulled the hand off his leg.  
“What the fuck? You’re supposed to be on my side.”

“I’m sorry, but, it’s not even like they’re dating,” Mattsun explained, “I think Iwaizumi would probably freak out if Oikawa suddenly started feeling him up under the table.”

“Feeling him- Feeling him up? I wasn’t _feeling you up_ it was a gesture of _love_. It was _romantic_. You both just have fucking filthy minds.”

“You were six inches from my dick Makki, I don’t think that’s romantic.”

Makki rolled his eyes, “Oh fuck off, that was perfectly normal! You’re just so horny for me you’d probably get a boner if I held your hand.”

Heat flushed over Mattsun’s face. Where the fuck had that come from? How the hell did they get to this? And why did it seem like Oikawa was not even close to a part of this conversation? Mattsun was lost, and though his mouth was open, he couldn’t find a single word to make it say.

“I forgot how gross the bathrooms are here,” Iwaizumi noted as he slid back into his seat. When no one responded, his eyes scanned the faces of his three friends, “Did I miss something?”

“Nope, nothing,” Mattsun answered as quickly as possible, shaking his head in what he hoped looked like a casual way. He didn’t want to give Oikawa or Makki the chance to say anything weird or passive aggressive, the heat on his face was already starting to get unmanageable, “I don’t think you finished your interview story, though. Did you get the job?”

* * *

Mattsun and Makki didn’t talk about their fight on new years day, but they also stopped doing their little _flirting for dummies_ thing, and it was pretty obvious why. 

Honestly Mattsun would be happy to pretend none of it ever happened. He couldn’t believe he’d let the joke go that far. He couldn’t believe he’d blushed because Makki had touched him. Fucking Makki.

It seemed like the joke hadn’t done much to help Oikawa and Iwaizumi’s relationship either. If anything it might have made them both more guarded, because soon graduation was approaching and neither of them had made a move.

They were at a party, Matsukawa’s party, because his parents were out of town and his house was fucking massive and they were _graduating_ for god’s sake, when Mattsun found Makki talking to Oikawa, on the couch.

Honestly, Mattsun had been sort of avoiding situations where he would be alone with Makki all night, a little cautious given the last time he’d been drinking alcohol and hanging out with his best friend, but Oikawa was there. Things couldn’t get that bad with Oikawa there.

If he had been thinking straight he might have remembered Oikawa had also been there last time, and it had not helped at all, but he wasn’t thinking straight. He had just finished his fourth beer.

“Please, Oikawa, you have to say something,” Makki’s voice was loud even over the music pulsing through the room. He was probably on his fourth or fifth drink, too, “You’re going to Brazil, dude, it’s now or never!”

Mattsun draped himself over the back of the couch, leaning into their conversation. He knew what they were talking about without having to ask.

“He’s right bro,” Mattsun admitted, feeling a little glad his arms were braced against the couch, because the room seemed to sway as he bent over, “Iwaizumi deserves to know before you go.”

Oikawa sighed, eyes closed and head back against the couch, “Thanks for your input Mattsun, but I really didn’t ask.”

“Oh come on,” Makki urged, shoving Oikawa’s shoulder, “What are you so afraid of?”

“Hmm, I don’t know,” Oikawa mused, opening his eyes and turning to Makki, he seemed more sober, probably two drinks in if Mattsun had to guess, “Maybe that he’ll reject me. Maybe that he’ll think I’m weird, and creepy. Maybe that I’ll ruin our friendship right before I leave and I’ll never get the chance to salvage it and then I’ll lose my best friend in the entire world.”

Mattsun and Makki were silent for a second, but they slowly turned their heads to look at each other and started sputtering laughter.

“That’s not gonna happen,” Mattsun said with a grin.  
“Yeah, he’s fucking in love with you, dumbass,” Makki agreed.

“He’s not,” Oikawa whined, flipping his hands around in frustration. Ok, so maybe he’d had three drinks, “I think I know my Iwa-chan better than you guys, and I know he doesn’t like me.”

Makki rolled his eyes.  
“So what,” he shouted in Oikawa’s face, “Even if he doesn’t, you’ll get rejected, it’s not that big a deal.”

As if to punctuate his point, Hanamaki turned around on the couch, bringing one knee up on the cushion so he could fully reach around to the other side. A little look, one that Mattsun couldn’t quite read, was the only warning he got before Makki surged up, wrapping one hand around the back of Mattsun’s neck to hold him in place as he kissed him.

His mouth opened and sucked a little on Mattsun’s bottom lip, pulling his mouth open, too. Makki tilted his head a little more, joining their lips at an angle and letting his tongue swipe once against Mattsun’s before he dropped his hand from the back of his neck and let himself fall back down on the couch.

He turned to Oikawa, “See? It’s not a big deal.”

Mattsun’s head was full of… something. Beer? Love? Lust? Something. Whatever it was it was making his thoughts fuzzy, and he couldn’t figure out what Makki was saying. The only thing he could figure out was that they’d barely started kissing. He definitely couldn’t figure out why they’d stopped.

He shifted his weight onto his right arm, so that his left one could snake down, connect with Makki’s jaw, and turn him away from Oikawa, turn him back to himself. He leaned further over the couch, closing his eyes as he joined their lips back together. Makki had caught him by surprise before. This time was going to be better.

Honestly, Mattsun forgot Oikawa was there. He forgot that actually, half their school year was in his living room, drinking beer and waiting for something interesting to happen, something they could gossip about. It wouldn’t have really mattered if he remembered though, it was worth being gossiped about, kissing Makki like this.

He pulled him a little closer, and felt Makki’s face push against him a bit as he brought his other knee up on the couch, too, fully facing Mattsun and sitting up high enough that he didn’t have to break his back bending over. It felt good, that Makki was leaning into it, that he seemed just as in control of the situation as Mattsun was, that he seemed to like it just as much.

Half the room was staring at them when they finally broke the kiss, especially Oikawa, who was sitting beside Makki on the couch with eyes so wide they looked like golf balls. Mattsun didn’t really care though, he just huffed a couple heavy breaths to catch up on the one’s he’d missed while kissing Makki, and Makki seemed to care even less, smiling up at Mattsun with a little glitter in his eyes.

“You were supposed to reject me,” he said, a little quietly for four-drink-Makki.  
“I was?” Mattsun breathed, still panting just a little.  
“It’s ok,” Makki grinned, leaning up to kiss him just once more, softly, "this is better."

Silence fell for a minute. Well, as close to silence as you can get at a graduation party with over a hundred people and music blasting from every speaker in the house. It felt like silence though. It felt peaceful.

“Huh,” Oikawa finally huffed, making his two friends look over, “So, you actually are?”

Makki scoffed, wrapping his arm around Mattsun’s head and pulling it close to him, fingers playing with his ear, like he had months ago. “That’s what I’ve been telling you this entire time.”

“Yeah, why would we fuck with you?” Mattsun grinned, maybe getting the joke a little more this time, “We’re your friends.”

**Author's Note:**

> I wrote this in one sitting and wanted to post it before I went out, but I did not edit, so if I read it back later and realise it's garbage I may change a bunch.


End file.
